HARRISBURG, Pa. (AP) – Three of the four candidates in Pennsylvania’s Democratic primary race for U.S. Senate are now being supported by an outside political action committee.

The group named 15104 disclosed Monday that it is spending more than $100,000 on TV ads to support John Fetterman. The committee’s name is a reference to the zip code of Braddock, the Pittsburgh-area steel town where Fetterman is the third-term mayor.

The group hasn’t disclosed the source of the money. The committee’s treasurer, Pat Millham, said that filing will be made according to the Federal Election Commission’s deadlines. The FEC says that deadline is July 15.

The Sunlight Foundation, which tracks political spending, says the money is being spent on TV ads at stations in the Harrisburg and Scranton media markets.